Stitching Together 2D Materials

While graphene is possibly the best known 2D material, it is not the only one and not all atom-thick materials behave the same. While graphene conducts electricity exceedingly well, hexagonal boron nitride (h-BN) is an insulator. Now researchers at Rice University have developed a way to precisely combine the two materials, and this work could lead to fully functional 2D circuits.

While its conductivity is part of the reason so many researchers are trying to incorporate graphene into electronics, it is also a challenge for them as conductors alone cannot build a circuit. The same can be said of insulators, such as h-BN, so a means to combine them is very valuable. To do so, the researchers first produce a layer of h-BN with chemical vapor deposition (CVD) and, with masks and ion beams they etch part of it away. Once the etching is complete, the researchers use a CVD process again, but this time they grow graphene, which attaches to the h-BN and fills the etched openings.

When completed, the two materials are connected but retain their original properties, so the graphene still conducts and the h-BN still insulates. Next the researchers want to add a semiconductor to the process, to create fully functional, 2D electronic circuits at the nanoscale.